Mechanical properties and thermomechanical stability of diamond-like carbon films synthesized by pulsed vacuum arc plasma deposition

The higher sp3 bonding fraction hydrogen-free diamond-like carbon (DLC) films were deposited on Si(1 0 0) and Cr17Ni14Cu4 stainless steel substrates by pulsed vacuum arc plasma deposition as a function of bias substrate voltage. The results show that the sp3 content increases slightly with higher substrate bias and the effective microhardness only increases slightly. The wear resistance of the as-deposited DLC films decreases with increasing substrate bias. The effective hardness of the annealed DLC films diminishes by approximately 20% and the wear resistance decreases after annealing at 400 °C due to local adhesion decreases, even though the wear resistance of the annealed DLC films is still much better than that of the Cr17Ni14Cu4 substrate. The thermomechanical stability of hydrogen-free DLC films synthesized by pulsed vacuum arc plasma deposition is better than the DLC films containing hydrogen synthesized by PECVD.